Nanosight has brought out software for its Nanoparticle Tracking Analysis (NTA) system, which analyses particles as they are detected.
New software versions usually offer fixes to problems and slight tweaks to existing routines in response to user requests.
Extended Analysis answers two questions for users of NTA: how long should a user run an analysis and how many particles does the user need to measure to get a statistically good result? The two are interdependent: the longer the analysis time, the more particles are counted, as the contents of the interrogated volume self-refresh through diffusion.
NTA 2.0 now analyses particles as they are detected, eliminating the need to record for post-experiment analysis, speeding use and repeatability.
Users may now run analyses for far longer and improve the development of the optimal analysis time.
Extended dynamic range is achieved through the interleaving of alternate video frames at high and then low gain settings, helping users track large and small particles in the same sample, greatly increasing dynamic range.
For example, four clear peaks are readily observed for a mix of latex reference particles of 50, 200, 400 and 590nm.
The 3D diameter scatter plot shows diameter plotted against scatter intensity to boost resolution and provide a capability to differentiate similar sized particles when they are of differing materials.
In these analyses, a third axis plots scatter intensity against the existing particle size distribution of number count against size.
The last new benefit is derived from model-fitting.
This enhancement compensates for the natural broadening of displayed results.
This broadening is inherent in the stochastic nature of Brownian motion and the physical limitation of only being able to track particles for a finite number of frames.
Model-fitting works by compensating for the number of tracks (consecutive jumps, frame to frame) used in the NTA analysis.
This effectively compensates for the Gaussian breadth of the curve where its origin is understood.
Users are able to apply this feature to specific peaks displayed in the particle size analysis.
